The present invention relates to a gas insulated switch-gear apparatus, and more particularly to an improvement of a gas insulated switch-gear apparatus which is suitable for use in a substation of small floor space and which is easy to install, maintain and inspect.
The gas insulated switch-gear apparatus which uses SF.sub.6 gas as insulating medium has an advantage of considerable reduction of insulation distance but may require a large floor space depending on a particular arrangement of the apparatus.
Recently, it has become difficult for the substation in which the gas insulated switch-gear apparatus is mounted to assure a wide ground and hence an arrangement of the apparatus which enables considerable reduction of floor space for mounting has been desired.
In order to meet the above requirement, it has been proposed to arrange an apparatus of different one of three phasees on each story of a building, arrange a plurality of circuit breakers between two parallel busbars, and arrange disconnecting switches between th circuit breakers and the busbars and external terminals, respectively so that various distribution networks can be constructed (see U.S. Pat. No. 3,302,069 to Wilcox, or it has been proposed to electrically interconnect electric equipments in a substation including transformers, circuit breakers and disconnecting switches through a ring busbar and accommodate the assembly at different vertical spatial levels of a sectioned building (see U.S. Pat. No. 3,378,731 to Whitehead), or it has also been proposed to provide first and second base phanes arranged in parallel to each other at different vertical spatial levels, on which base planes necessary electric facilities such as circuit breakers are mounted, and arrange a gas insulated busbar between those base planes closely to the second base plane which lies above the first base plane (see Japanese Utility Model Publication No. 11312/71).
Although those proposals can considerably reduce the floor space for mounting by multi-story construction, they still have problems of necessitating much time and manpower for the installation, maintenance and inspection of the apparatus because of the complexity of the arrangement of the electric equipments and the busbars of the respective stories.